Genetic immunization, also known as DNA or nucleic acid vaccination, is an immunization method whereby, in contrast to conventional immunization, antigen-coded nucleic acids rather than antigens are injected and the immunization reaction then acts counter to the protein which is generated. Such vaccination with nucleic acids is typically conducted in humans or in animals by injection or by ballistic transmission, i.e., by a so-called “gene-gun.” Pure or so-called “naked” DNA is administered generally in the form of plasmids. The DNA migrates through unknown pathways into the cells of the patient's body, thereby penetrating to the cores of the cells. In the core, the DNA transcribes (constructs a messenger RNA molecule using the DNA molecule as a template, resulting in transfer of the genetic information to the RNA) and the resulting messenger RNA (mRNA) subsequently translates (forms a protein molecule at a ribosomal site of protein synthesis from information contained in the mRNA) into the cytoplasm, whereupon the protein generated thereby releases the immunological response. In the case of humans, very frequently the promoter of the human cytomegalovirus (CMV) is employed as an adjuvant or control element for various DNA types. There are, however, other useful adjuvants, both for humans and animals, such as SV40. In the case of RNA types, ribosomes may be also used as adjuvants.
The genes necessary for immune response, which are coded for the significant proteins, can be prepared in sufficient quantities for use on plasmids in, for example, microorganisms such as E. coli. With the aid of the plasmid technology, it is possible to transfer only the genes, resulting in an effective, side effect-free immune response. Plasmids themselves can also be multiplied relatively simply in E. coli. The quality demands on the genetic materials for injection include homogeneity and freedom from endotoxins in addition to the customary requirements for purity and freedom from proteins.
For genetic vaccination, the injection is conventionally an aqueous solution of the active agent packaged in an ampoule, from which the injection is withdrawn into a syringe and administered. A major drawback of such a vaccination is that nucleic acids are seldom stable in aqueous solutions. Accordingly, for shipment and storage, substantial preventive measures must be taken. A second drawback is that warm climates drastically reduce the effectiveness of such injection solutions.
Accordingly it is a primary goal of the present invention to provide a device for genetic vaccination that permits the transport and storage of the DNA vaccine simply and that avoids the aforementioned drawbacks of the prior art, and to provide a process of forming a genetic vaccine that is similarly free of the prior art drawbacks.